package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.util.BooleanUtil;
import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.hmdp.dto.Result;
import com.hmdp.dto.ScrollResult;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Blog;
import com.hmdp.entity.Follow;
import com.hmdp.entity.User;
import com.hmdp.mapper.BlogMapper;
import com.hmdp.service.IBlogService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IFollowService;
import com.hmdp.service.IUserService;
import com.hmdp.utils.SystemConstants;
import com.hmdp.utils.UserHolder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.ZSetOperations;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.*;
import java.util.stream.Collectors;

import static com.hmdp.utils.RedisConstants.BLOG_LIKED_KEY;
import static com.hmdp.utils.RedisConstants.FEED_KEY;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IBlogService {

    @Resource
    private IUserService userService;

    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    @Autowired
    private IFollowService followService;

    @Override
    public Result queryBlogById(Long id) {
        Blog blog = getById(id);
        if(blog==null){
            return Result.fail("笔记不存在");
        }
        queryBlogUser(blog);
        isBlogLike(blog);
        return Result.ok(blog);

    }

    @Override
    public Result queryHotblog(Integer current) {
        // 根据用户查询
        Page<Blog> page = query()
                .orderByDesc("liked")
                .page(new Page<>(current, SystemConstants.MAX_PAGE_SIZE));
        // 获取当前页数据
        List<Blog> records = page.getRecords();
        // 查询用户
        records.forEach(blog -> {
            isBlogLike(blog);
            queryBlogUser(blog);
        });
        return Result.ok(records);
    }


    private void queryBlogUser(Blog blog) {
        Long userId = blog.getUserId();
        User user = userService.getById(userId);
        blog.setName(user.getNickName());
        blog.setIcon(user.getIcon());
    }

    private void isBlogLike(Blog blog){
        UserDTO user = UserHolder.getUser();
        if(user==null){
            return;
        }
        Long userId = user.getId();
        String key="blog:liked:"+blog.getId();

        Double score = stringRedisTemplate.opsForZSet().score(key, userId.toString());
        blog.setIsLike(score!=null);

    }

    @Override
    public Result likeBlog(Long id) {
        Long userId = UserHolder.getUser().getId();
        String key="blog:liked:"+id;
        Double score = stringRedisTemplate.opsForZSet().score(key, userId.toString());
        if(score==null){
            boolean isSuccess = update().setSql("liked=liked+1").eq("id", id).update();
            if(isSuccess){
                stringRedisTemplate.opsForZSet().add(key,userId.toString(),System.currentTimeMillis());
            }
        }else{
            boolean isSuccess = update().setSql("liked=liked-1").eq("id", id).update();
            if(isSuccess){
                stringRedisTemplate.opsForZSet().remove(key,userId.toString());
            }
        }
        return Result.ok();

    }

    @Override
    public Result queryBloglikes(Long id) {

        String key=BLOG_LIKED_KEY +id;

        Set<String> top5 = stringRedisTemplate.opsForZSet().range(key, 0, 4);
        if(top5==null||top5.isEmpty()){
            return Result.ok(Collections.emptyList());
        }
        List<Long> ids = top5.stream().map(Long::valueOf).collect(Collectors.toList());
        String idStr = StrUtil.join(",", ids);
        List<UserDTO> userDTOS = userService.query()
                .in("id",ids).last("order by field(id,"+idStr+")").list()
                .stream()
                .map(user -> BeanUtil.copyProperties(user, UserDTO.class))
                .collect(Collectors.toList());

        return  Result.ok(userDTOS);

    }

    @Override
    public Result saveBlog(Blog blog) {

        // 获取登录用户
        UserDTO user = UserHolder.getUser();
        blog.setUserId(user.getId());
        // 保存探店博文
         save(blog);
        List<Follow> follows = followService.query().eq("follow_user_id", user.getId()).list();

        for (Follow follow : follows) {
            Long userId = follow.getUserId();

            String key="feed:"+userId;
            stringRedisTemplate.opsForZSet().add(key,blog.getId().toString(),System.currentTimeMillis());
        }
        // 返回id
        return Result.ok(blog.getId());
    }

    @Override
    public Result queryBlogOfFollow(Long max, Integer offset) {
        Long userId = UserHolder.getUser().getId();

        String key =FEED_KEY+userId;

        Set<ZSetOperations.TypedTuple<String>> typedTuples = stringRedisTemplate.opsForZSet()
                .reverseRangeByScoreWithScores(key, 0, max, offset, 2);

        if(typedTuples==null||typedTuples.isEmpty()){
            return Result.ok();
        }
        List<Long> ids=new  ArrayList<>(typedTuples.size());
        long minTime=0;
        int os=1;

        for (ZSetOperations.TypedTuple<String> typedTuple : typedTuples) {
            ids.add(Long.valueOf(typedTuple.getValue()));
            long time = typedTuple.getScore().longValue();

            if(time==minTime){
                os++;
            }else{
                minTime=time;
                os=1;
            }
        }
        String idStr = StrUtil.join(",", ids);

        List<Blog> blogs = query()
                .in("id", ids).last("order by field(id," + idStr + ")").list();
        for (Blog blog : blogs) {
            queryBlogUser(blog);
            isBlogLike(blog);
        }
        ScrollResult r = new ScrollResult();
        r.setList(blogs);
        r.setOffset(os);
        r.setMinTime(minTime);

        return Result.ok(r);


    }


}
